Listen to a narrated version of this essay: It didn’t dawn on me that there might be a few holes in my education until I was about 35. I’d just bought a house, the pipes needed fixing, and the plumber was standing in my kitchen. There he was, a short, beefy guy with a goatee and a Red Sox cap and a thick Boston accent, and I suddenly learned that I didn’t have the slightest idea what to say to someone like him. So alien was his experience to me, so unguessable his values, so mysterious his very language, that I couldn’t succeed in engaging him in a few minutes of small talk before he got down to work. Fourteen years of higher education and a handful of Ivy League degrees, and there I was, stiff and stupid, struck dumb by my own dumbness. “Ivy retardation,” a friend of mine calls this. I could carry on conversations with people from other countries, in other languages, but I couldn’t talk to the man who was standing in my own house.…